Wireless communication device and information-processing apparatus which can hold the device

ABSTRACT

A wireless communication device to be removably held in a host apparatus. The wireless communication device comprises a printed circuit board, a cover, and a planar antenna module. The printed circuit board comprises electronic components configured to perform wireless communication. The cover covers the electronic components and the upper surface of the board. The planar antenna module has an electromagnetic radiation surface and is provided in the upper surface of the cover such that it is substantially flush with an outer surface of the host apparatus during operation of the wireless communication device.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is based upon and claims the benefit of priority fromthe prior Japanese Patent Application No. 2001-335421, filed Oct. 31,2001, the entire contents of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a wireless communication device and aninformation-processing apparatus that can hold the device.

2. Description of the Related Art

In recent years, wireless communication devices have come to be mountedin mobile information-processing apparatuses such as notebook-typepersonal computer and PDAs. To mount a wireless communication device inan information-processing apparatus, two methods may be used. A firstmethod is to incorporate the wireless communication device into thehousing of the information-processing apparatus. The second method is toinsert the device in the form of a PC card into a PC card slot providedin the housing of the information-processing apparatus. The secondmethod is preferable in view of the manufacturing cost of the mobileinformation-processing apparatus. This is because the PC card (i.e.,wireless communication device) is an optional unit, which the user buysand inserts into the PC card slot after he or she has bought the mobileinformation-processing apparatus.

Jpn. Pat. Appln. KOKAI Publication No. 10-283449 discloses a wirelesscommunication card shaped like a PC card. The wireless communicationcard is an extended-type PC card. While inserted in the PC card slot ofa mobile information-processing apparatus, the card has its extendedpart protruding from the housing of the apparatus. The antenna of thewireless communication card is incorporated in the extended part inorder to enhance the wireless communication efficiency.

Another wireless communication card is described in U.S. Pat. No.5,867,131. An antenna is mounted on a dielectric card. The antenna cardmay be hingeable or slideably mounted to a mobile computer. The antennacard is storable in a recess in the display portion of the mobilecomputer when not in use. When in use, the antenna card is eitherrotatably or slideably extended to a deployed position away from thedisplay portion of the mobile computer.

In all of the wireless communication cards discussed above, the extendedpart, which protrudes from the housing of the apparatus, is notresistant to mechanical impacts. The extended section may be greatlydamaged by an impact, depending on the direction of the impact. It maybe broken if the user accidentally drops it onto the floor or hits itagainst anything hard. If this should happen, not only the housing ofthe extended part, but also the antenna and electronic components thatare provided in this part may be broken.

BRIEF SUMMARY OF THE INVENTION

Embodiments of the present invention provide a wireless communicationdevice that can reliably perform its function while held in a hostapparatus, without having its antenna protruding from the housing of theapparatus.

According to an embodiment of the present invention, there is provided aplanar antenna to be removably held in a surface of a host apparatushaving a wireless communication function. The planar antenna comprisesan electromagnetic radiation surface that is substantially flush with asurface of the host apparatus during wireless communication.

According to another embodiment of the present invention, there isprovided a wireless communication device removably held in a hostapparatus. The wireless communication device comprises a planar antennamodule having an electromagnetic radiation surface substantially flushwith a surface of the host apparatus during operation of the wirelesscommunication device. According to one embodiment of the presentinvention, the surface of the host apparatus is an outer surface suchthat the electromagnetic radiation surface is substantially flush withthe outer surface during operation of the wireless communication device.

According to other embodiments of the present invention, the wirelesscommunication device comprises a printed circuit board includingelectronic components configured to perform wireless communication. Inone embodiment, a cover is provided for covering the printed circuitboard and the electronic components. The planar antenna module may beprovided in an upper surface of the cover such that when the wirelesscommunication device is held in the host apparatus the upper surface ofthe cover and the electromagnetic radiation surface are substantiallyflush with the surface of the host apparatus. In one embodiment, theupper surface of the cover has a recess, and the planar antenna moduleis embedded in the recess and the cover has an inner surface coveredwith a metal layer.

In further embodiments of the present invention, a connector is providedon a lower surface of the printed circuit board and is configured toconnect the printed circuit board to the host apparatus.

In still further embodiments of the present invention, a power source isremovably mounted on a lower surface of the printed circuit board forsupplying electric power to the electronic components. In oneembodiment, the power source is a battery. In another embodiment, thepower source is one or more solar cells. In further embodiments, thepower source may be a combination of at least one battery and one ormore solar cells.

According to one embodiment, the host apparatus is aninformation-processing apparatus for performing wireless communication.The information-processing apparatus comprises a housing, a display unitrotatable, with respect to the housing, between an opened position and aclosed position, and having a front surface and a back surface, the backsurface having a recess therein. The wireless communication device isremovably provided in the recess and includes a planar antenna modulehaving an electromagnetic radiation surface substantially flush with theback surface of the information-processing apparatus during operation ofthe wireless communication device.

Additional features and advantages of the invention will be set forth inthe description which follows, and in part will be obvious from thedescription, or may be learned by practice of the invention. The objectsand advantages of the invention may be realized and obtained by means ofthe instrumentalities and combinations particularly pointed outhereinafter.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

The accompanying drawings, which are incorporated in and constitute apart of the specification, illustrate embodiments of the invention, andtogether with the general description given above and the detaileddescription of the embodiments given below, serve to explain theprinciples of the invention.

FIG. 1 is a rear, perspective view showing a wireless communicationdevice according to a first embodiment of the invention, and a computerthat can hold the wireless communication device, having its display unitopened;

FIG. 2 is a rear, perspective view showing the computer and the devicebeing held in a surface of the display unit of the computer, accordingto embodiments of the present invention;

FIG. 3 is a cross-sectional view illustrating an example of the displayunit of the computer, according to embodiments of the present invention;

FIG. 4 is an exploded view of the wireless communication deviceaccording to a first embodiment of the present invention;

FIG. 5 is a cross-sectional view depicting the structure of the wirelesscommunication device according to the first embodiment of the presentinvention;

FIG. 6 is a cross-sectional view of the planar antenna provided in thedevice according to the first embodiment of the present invention;

FIG. 7 is a block diagram of a system that comprises the wirelesscommunication device according to the first embodiment of the presentinvention and the computer that can hold the wireless communicationdevice;

FIG. 8 is a cross-sectional view of a wireless communication deviceaccording to a second embodiment of the present invention;

FIG. 9 is a perspective view of the wireless communication deviceaccording to the second embodiment of the present invention;

FIG. 10 is a block diagram of a system that comprises the wirelesscommunication device according to the second embodiment of the presentinvention and the computer that can hold this wireless communicationdevice;

FIG. 11 is a cross-sectional view of a wireless communication deviceaccording to a third embodiment of the present invention;

FIG. 12 is a perspective view of the wireless communication deviceaccording to the third embodiment of the present invention; and

FIG. 13 is a block diagram of a system that comprises the wirelesscommunication device according to the third embodiment of the presentinvention and the computer that can hold the wireless communicationdevice.

DETAILED DESCRIPTION OF THE INVENTION

Embodiments of the present invention will be described, with referenceto the accompanying drawings.

A wireless communication device according to a first embodiment of theinvention and an information-processing apparatus that can hold thewireless communication device will be described, with reference to FIGS.1 and 2. The information-processing apparatus is, for example, a mobileapparatus such as, but not limited to, a notebook-type personal computeror a PDA. Hereinafter, the apparatus will be described as anotebook-type personal computer 1.

FIG. 1 shows the notebook-type personal computer 1 as viewed from therear and having its display unit opened. The computer 1 comprises ahousing 101 and a display unit 102. The display unit 102 incorporates aflat panel display that is an LCD (Liquid Crystal Display). The displayunit 102 is hinged to the housing 102 and can be rotated, with respectto the housing 101, between an opened position and a closed position.

The housing 101 is shaped like a shallow rectangular box. Input devices,such as a keyboard and a pointing device, are arranged on the uppersurface of the housing 101. A display hinge 104 is secured to the rearedge of the upper surface of the housing 101. The display hinge 104supports the display unit 102 to the housing 102, allowing the displayunit 102 to rotate between the opened position and the closed position.

The display unit 102 has a recess 103 in its back. The recess 103 canaccommodate a wireless communication device 2. A printed circuit board(not shown) lies on the bottom of the recess 103 to connect the wirelesscommunication device 2 to the personal computer 1.

The wireless communication device 2 is a module that comprises ahousing, some electronic components and an antenna. The electroniccomponents and the antenna cooperate to perform wireless communication.The housing of the wireless communication device 2 has such shape andsize as can be fitted in the recess 103 made in the back of the displayunit 102 of the personal computer 1. Since the recess 103 defines asubstantially rectangular space, the housing of the wirelesscommunication device 2 is a rectangular box that is almost as large as(i.e., a little smaller than) the recess 103. The wireless communicationdevice 2 has a planer antenna module 3, which is embedded in the uppersurface of the housing. The planer antenna module 3 has anelectromagnetic radiation surface. The radiation surface is exposedoutside and substantially flush with the upper surface of the housing ofthe wireless communication device 2.

The planar antenna module 3 has a relatively high directivity. Theregion that the module 3 can cover to receive radio waves tends to liein the front of the electromagnetic radiation surface (i.e., at the backof the display unit 102), rather than at the hack of the radiationsurface (i.e., in front of the display unit 102). Nonetheless, theplanar antenna module 3 can also cover a region lying at the back of theradiation surface. This is because the recess 103 made in the back ofthe display unit 102 is located near the upper edge thereof.

FIG. 2 shows the personal computer 1 that holds the wirelesscommunication device 2. As illustrated in FIG. 2, the wirelesscommunication device 2 is fitted in the recess 103 cut in the back ofthe display unit 102. While held in the recess 103, the upper surface ofthe wireless communication device 2 is substantially flush with the backof the display unit 102 and does not project from the display unit 102.Hence, the back of the display unit 102 is flat and smooth as a whole.Since its electromagnetic radiation surface is exposed in its entirety,the planer antenna module 3 can advantageously achieve efficient radiocommunication, though its antenna section does not protrude from thedisplay unit 102 of the personal computer 1.

The wireless communication device 2 is an optional one that can beinserted and removed into and from the recess 103. The recess 103 may befilled with a cap made of, for example, rubber, while the device 2 isnot being used in combination with the personal computer 1. If this isthe case, the back of the display unit 102 can be flat and smooth as awhole.

FIG. 3 is a cross-sectional view of the display unit 102, showing therecess 103 and some components of the unit 102, which lie near therecess 103.

The display unit 102 comprises an outer wall 102 a that defines the backof the unit 102. The outer wall 102 a has a rectangular opening, throughwhich the wireless communication device 2 can be inserted into therecess 103. The display unit 102 contains a flat panel display 106. Theflat panel display 106 is arranged, with its back opposing the back ofthe display unit 102. A metal plate 105 covers the entire back of theflat panel display 106. The metal plate 105 serves as the frame of theflat panel display 106. The printed circuit board 18, mentioned earlier,lies between the outer wall 102 a and the metal plate 105. The printedcircuit board 18 has a connector 16 that can connect the wirelesscommunication device 2 to the personal computer 1. The space between theprinted circuit board 18 and the wall 102 a, which opens at the wall102, is the recess 103.

The wireless communication device 2 has a connector 10 on the lowersurface. The connector 10 contacts the connector 16 provided in the flatpanel display unit 106, as long as the wireless communication device 2remains in the recess 103. The wireless communication device 2 is thusconnected to the personal computer 1, mechanically and electrically.

The metal plate 105 can shield electromagnetic waves. It can thereforeminimize the influence that the electromagnetic waves emanating from thewireless communication device 2 may impose on the electronic componentsof the computer 1.

The wireless communication device 2 will now be described in terms ofits structure.

FIG. 4 is an exploded view of the wireless communication device 2. As isillustrated in FIG. 4, the wireless communication device 2 includes acover 2 a and a printed circuit board 6. The cover 2 a covers theprinted circuit board 6. The cover 2 a is a rectangular case that opensat the lower surface. The planer antenna module 3 is embedded in theupper surface of the cover 2 a, with its electromagnetic radiationsurface exposed to the outside of the computer 1. The planer antennamodule 3 has an insulating base that is a thin plate that may be about 4mm thick. One surface of the insulating base functions as theelectromagnetic radiation surface. The planar antenna module 3 is, forexample, a patch antenna that is one type of a micro-strip antenna.

A contact 4 a lies on the electromagnetic radiation surface of theplanar antenna module 3. The contact 4 a connects the radiation surfaceto a conduction path that penetrates the insulating base. Moreprecisely, the contact 4 a is connected to the feeding terminal 5provided on the back of the planar antenna module 3. The feedingterminal 5 extends from the lower surface of the cover 2 a and isconnected to the antenna terminal 11 mounted on the printed circuitboard 6 via a wiring cable (not shown). A land or connector 17 that isprovided on the printed circuit board 6 connects the antenna terminal 11to the wiring cable.

The printed circuit board 6 is a hard plate. It holds a wirelesscommunication IC 7 on its surface. A quartz oscillator 8, a flash EEPROM9, and other electronic components 12 to 15 are also mounted on theprinted circuit board 6. Among the electronic components 12 to 15 are,for example, chip resistors and chip capacitors. The wirelesscommunication IC 7 is the main electronic component provided on theprinted circuit board 6 and is designed to implement wirelesscommunication. The IC 7 is a one-chip LSI comprising an RF section and abase-band section. The RF section performs upward conversion, convertingan intermediate frequency to an RF frequency. The RF section alsoperforms downward conversion, from an RF frequency to an intermediatefrequency. The base-band section modulates data to transmit anddemodulates data received, in accordance with a prescribed protocol ofwireless communication. The quartz oscillator 8 generates the operatingclock signal of the wireless communication IC 7. The flash EEPROM 9stores the firmware that controls the wireless communication IC 7. Thefirmware is a program that describes the sequence of protocol stacks forcontrolling the operation of the base-band section.

The printed circuit board 6 serves as the base of the wirelesscommunication device 2. The printed circuit board 6 holds a connector 10(i.e., plug) on its lower surface. The connector 10 can be connected tothe connector 16, or receptacle (e.g., stacking connector), mounted on aprinted circuit board 18. The printed circuit board 18 is provided inthe back of the display unit 102 of the personal computer 1.

FIG. 5 is a cross-sectional view of the wireless communication device 2.

The cover 2 a covers the upper surface of the printed circuit board 6and, hence, all electronic components mounted on the upper surface ofthe printed circuit board 6. The planar antenna module 3 is embedded inthe upper surface of the cover 2 a, with its electromagnetic radiationsurface lying substantially flush with the upper surface of the cover 2a. In other words, the cover 2 a has a recess in its upper surface andthe planar antenna module 3 is held in the recess. As FIG. 6 shows, themodule 3 comprises a base 301 and a metal layer 302. The base 301 ismade of insulating material such as resin. The metal layer 302 (alsoknown as “patch”) may be made, for example, by forming a copper foil onthe base 301 and then plating the copper foil with gold. The feedingterminal 5 protrudes from the lower surface of the base 301.

The cover 2 a is also made of insulating material. As FIG. 5 depicts, ametal layer 2 b formed by, for example, plating, covers the entire innersurface of the cover 2 a. The metal layer 2 b functions as anelectromagnetic shield to the electronic components mounted on theprinted circuit board 6. The cover 2 a has its lower surface bonded withan adhesive or the like to the upper surface of the printed circuitboard 6.

While the connector 10 of the wireless communication device 2 remainsconnected to the connector 16 set in the recess 103, a space exists inthe recess 103, at the back of the printed circuit board 6. In thisspace lies a cell box 3 d that contains a button cell 3 c. The buttoncell 3 c can be removed from the cell box 3 d. The button cell 3 ccomprises at least one battery to supply electric power to theelectronic components mounted on the upper surface of the printedcircuit board 6. Thanks to the button cell 3 c, no power needs to besupplied to the wireless communication device 2 from the personalcomputer 1. It therefore suffices to arrange signal pins between thecomputer 1 and the wireless communication device 2. That is, power neednot be supplied from the computer 1 to the wireless communication device2. Locating the cell box 3 d in the lower surface of the printed circuitboard 6 achieves an efficient use of the recess 103 and renders itunnecessary to supply power from the computer 1 to the wirelesscommunication device 2.

According to embodiments of the present invention, the button cell 3 ccomprises at least one battery which is rechargeable. In one embodiment,the battery may be removed from the wireless communication device 2 andrecharged, for example, in a separate recharging unit (not shown).

In another embodiment, the battery may remain in the wirelesscommunication device 2 and be recharged by a power source providingpower to the computer 1 (for example the output of the AC adapter 43 orthe battery (Li-ion) 42). According to this embodiment, a battery in thebutton cell 3 c can be recharged while the wireless communication device2 is provided in the computer 1. Appropriate power connections may beprovided between computer 1 and the wireless communication device 2 forrecharging the battery in the button cell 3 c. The recharging of thebattery in the button cell 3 c may be initiated through appropriatehardware and/or software means.

In the wireless communication device 2 according to the firstembodiment, the cover 2 a covers the printed circuit board 6 asindicated above. The planar antenna module 3 is embedded in the uppersurface of the cover 2 a, with its electromagnetic radiation surface 302exposed to the outside. Therefore, the wireless communication device 2is a two-layered structure that comprises a lower layer, i.e., printedcircuit board 6, and an upper layer, i.e., planar antenna module 3located above the printed circuit board 6. Further, the upper surface ofthe wireless communication device 2 is flat and smooth, because theplanar antenna module 3 is embedded in the upper surface of the cover 2a, i.e., the uppermost part of the wireless communication device 2.Thus, as long the wireless communication device 2 remains in the recess103, the antenna section does not project from the back of the displayunit 102 and the electromagnetic radiation surface 302, which lies onthe module 3, remains exposed to the outside of the computer 1. Thisimparts sufficient wireless communication efficiency to the wirelesscommunication device 2.

As described above, according to embodiments of the present inventionthe base of the planar antenna module 3 may be about 4 mm thick.According to one embodiment, only the upper half (about 2 mm thick) ofthe base 301 may be embedded in the recess of the cover 2 a. Even inthis case, the upper surface of the wireless communication device 2 issufficiently smooth.

FIG. 7 is a block diagram of a system that comprises the personalcomputer 1 and the wireless communication device 2.

The personal computer 1 has an engine section 34 that controls the othercomponents of the computer 1. The engine section 34 comprises a CPU 20,a flash memory 21, a DRAM 22, an EEPROM 23, a CPU bus 24 and a PCI bus25, and a bus bridge 26. The flash memory 21 stores programs includingBIOS. The DRAM 22 is the main memory of the computer 1. The EEPROM 23 isprovided to store various items of information such as, but not limitedto, configuration information. The bus bridge 26 connects the CPU bus 24and the PCI bus 25. The bus bridge 26 incorporates a memory controllerdesigned to control the flash memory 21 and the DRAM 22. The bus bridge26 also incorporates an interface unit, which functions as an interfacebetween the other components of the engine section 34 and a displaycontroller 38. The display controller 38 controls the flat panel display106.

The personal computer 1 comprises an IDE interface controller 27, a USBhost controller 28, a power-supply controller 29, a PCI/ISA bridge 30,an ISA bus 31, an I/O controller 32, various buttons 44, and a rotaryswitch 45. The controllers 27, 28 and 29 and the PCI/ISA bridge 30 areconnected to the PCI bus 25. The I/O controller 32 is connected to theISA bus 31 to control the buttons 44 and the rotary switch 45.

The computer 1 further comprises an HDD 33, a power-supply controlcircuit 41, and a battery (Li-ion) 42. The HDD 33 is connected to theIDE interface controller 27. The power-supply control circuit 41 and thepower-supply controller 29 constitute a power-supply section 40 thatcontrols the power supply in the personal computer 1. The power-supplycontrol circuit 41 generates an operating power from the battery 42 orthe output of the AC adapter 43. The operating power is supplied via thepower-supply controller 29 to the other components of the computer 1.

The wireless communication device 2 is a small wireless module thataccords with the short-distance wireless communication standard such asBluetooth™. A USB (Universal Series Bus) connects the wirelesscommunication device 2 to the personal computer 1. The USB hostcontroller 28 controls any external USB device to be connected to theUSB connector 36. Further, a USB interface line 35 connects thecontroller 28 to the connector 16 provided in the back of the displayunit 102.

The wireless communication device 2 (i.e., a Bluetooth™ module)comprises antenna 3, wireless communication IC 7, quartz oscillator 8,flash memory 9, and button cell 3 c, as indicated earlier. The wirelesscommunication IC 7 has an RF section 37 and a base-band section 39. Thebase-band section controls the wireless communication function ofBluetooth™. It performs the wireless communication between the wirelesscommunication device 2 and an external apparatus (not shown).

In one embodiment, the user can operate the rotary switch 45 to assign aPIN (Personal Identification Number) to the Bluetooth™ module 2.

A wireless communication device 2 according to a second embodiment ofthe invention will be described with reference to FIGS. 8 and 9. FIGS. 8and 9 are a cross-sectional view and a perspective view, respectively,of this wireless communication device.

The wireless communication device 2 has a solar cell module 3 b embeddedin the upper surface of the cover 2 a, whereas the wirelesscommunication device 2 of FIGS. 1 to 7 has a button cell 3 c provided onthe lower surface of the cover 2 a. In all other respects, the secondembodiment is identical to the first embodiment.

In the wireless communication device 2 according to the secondembodiment, the solar cell module 3 b converts light energy to electricenergy, which is supplied to the electronic components mounted on theprinted circuit board 6. Like the planar antenna module 3, the solarcell module 3 b is embedded in the upper surface of the cover 2 a. Thelight-receiving surface of the cell module 3 b lies substantially flushwith the upper surface of the cover 2 a. The module 3 b includes aplurality of solar cells (not shown). The solar cell module 3 b may beshaped like a ring to surround the circumferential surface of the planarantenna module 3.

A conducting path 100 penetrates the cover 2 a, connecting the solarcell module 3 b to the printed circuit board 6. The power the solar cellmodule 3 b has generated is supplied via the conducting path 100 to theelectronic components mounted on the printed circuit board 6.

The upper surface of the cover 2 a remains exposed while the wirelesscommunication device 2 is held in the recess 103 made in the back of thedisplay unit 102, as has been described with reference to FIGS. 1 to 7.The solar cell module 3 b, which is embedded in the upper surface of thecover 2 a, can efficiently receive light and can, hence, generateelectric power at high efficiency.

FIG. 10 is a block diagram of a system that comprises the wirelesscommunication device 2 according to the second embodiment and a personalcomputer 1. This personal computer 1 is identical to the personalcomputer 1 illustrated in FIG. 7. As described above, the solar cellmodule 3 b is used as a power supply in the wireless communicationdevice 2 according to the second embodiment. The power generated by thesolar cell module 3 b is supplied to the electronic components providedon the printed circuit board 6.

In the wireless communication device 2 of FIGS. 1 to 7 (the firstembodiment), the wireless communication device 2 must be removed fromthe recess 103 to be replaced by a new button cell. In the wirelesscommunication device 2 shown in FIG. 8 (the second embodiment), thesolar cell module 3 b need not be replaced as long as it functions well.Hence, the second embodiment is therefore more convenient than the firstembodiment.

A wireless communication device 2 according to a third embodiment ofthis invention will be described with reference to FIGS. 11 and 12.FIGS. 11 and 12 are a cross-sectional view and a perspective view,respectively, of this wireless communication device.

The third embodiment includes a cell box 3 d on the lower surface of theprinted circuit board 6 and a solar cell module 3 b embedded in theupper surface of the cover 2 a. A button cell 3 c can be set into andremoved from the cell box 3 d. In all other respects, the thirdembodiment is identical to the first embodiment.

FIG. 13 is a block diagram of a system that comprises the wirelesscommunication device 2 according to the third embodiment and a personalcomputer 1. This personal computer 1 is identical to the personalcomputer 1 illustrated in FIG. 7. In the third embodiment, the solarcell module 3 b and the button cell 3 c are used as power supplies. Thepower generated by the solar cell module 3 b and button cell 3 c issupplied to the electronic components provided on the printed circuitboard 6.

Having the button cell 3 c, the wireless communication device 2according to the third embodiment can operate in places where the solarcell module 3 b cannot receive sufficient light.

It is desirable to make the recess 103 in the back of the display unit102 as described above. Nonetheless, the recess 103 may be provided inone side of the housing 101 of the computer 1. It suffices to providethe recess 103 in a housing of the information-processing apparatus thatfunctions as the host apparatus to the wireless communication device 2.Then, the wireless communication device 2 can be provided in theapparatus, without protruding from the housing of the apparatus.

Additional advantages and modifications will readily occur to thoseskilled in the art. Therefore, the invention in its broader aspects isnot limited to the specific details and representative embodiments shownand described herein. Accordingly, various modifications may be madewithout departing from the spirit or scope of the general inventiveconcept as defined by the appended claims and their equivalents.

What is claimed is:
 1. A wireless communication device removably held ina host apparatus, said wireless communication device comprising: aprinted circuit board including electronic components configured toperform wireless communication; a cover which covers the printed circuitboard and the electronic components; and a planar antenna moduleprovided in an upper surface of the cover such that the planar antennamodule is opposed to the printed circuit board and arranged in parallelwith the printed circuit board, the planar antenna module having anelectromagnetic radiation surface substantially flush with a surface ofthe host apparatus during operation of the wireless communicationdevice, the electromagnetic radiation surface being electricallyconnected to the printed circuit board.
 2. The wireless communicationdevice according to claim 1, wherein the surface of the host apparatusis an outer surface such that the electromagnetic radiation surface issubstantially flush with the outer surface during operation of thewireless communication device.
 3. The wireless communication deviceaccording to claim 1, further comprising a connector provided on asurface of the printed circuit board and configured to connect theprinted circuit board to the host apparatus.
 4. The wirelesscommunication device according to claim 3, wherein the surface of theprinted circuit board is a lower surface of the printed circuit board.5. The wireless communication device according to claim 1, furthercomprising a power source removably mounted on the printed circuit boardand electrically connected thereto for supplying electric power to theelectronic components.
 6. The wireless communication device according toclaim 5, wherein the power source is rechargeable.
 7. The wirelesscommunication device according to claim 6, wherein the power sourceremains mounted on the printed circuit board during recharging andwherein the power source is recharged by a power source providing powerto the host apparatus.
 8. The wireless communication device according toclaim 1 further comprising a solar power source electrically connectedto the printed circuit board.
 9. The wireless communication deviceaccording to claim 5, wherein the power source is removably mounted on alower surface of the printed circuit board.
 10. The wirelesscommunication device according to claim 1, wherein the cover has aninner surface covered with a metal layer.
 11. The wireless communicationdevice according to claim 1, wherein the upper surface of the cover hasa recess, and the planar antenna module is provided in the recess. 12.The wireless communication device according to claim 1, furthercomprising a solar cell module provided in the upper surface of thecover, surrounding the planar antenna module and including a pluralityof solar cells for generating electric power to be supplied to theelectronic components.
 13. A wireless communication device removablyheld in a host apparatus, said wireless communication device comprising:a printed circuit board having an upper surface and a lower surface andincluding electronic components configured to perform wirelesscommunication, the electronic components being mounted on the uppersurface of the printed circuit board; a cover covering the upper surfaceof the printed circuit board and the electronic components; a connectorprovided on the lower surface of the printed circuit board andconfigured to connect the printed circuit board to the host apparatus;and a planar antenna module provided in an upper surface of the coversuch that the planar antenna module is opposed to the printed circuitboard and arranged in parallel with the printed circuit board, theplanar antenna module having an electromagnetic radiation surfacesubstantially flush with a surface of the host apparatus duringoperation of the wireless communication device, the electromagneticradiation surface being electrically connected to the printed circuitboard.
 14. An information-processing apparatus for performing wirelesscommunication, comprising: a housing having a surface and a recesstherein; and a wireless communication device removably provided in therecess, the wireless communication device comprising: a printed circuitboard having electronic components thereon configured to performwireless communication; a cover which covers the printed circuit boardand the electronic components; and a planar antenna module provided inan upper surface of the cover such that the planar antenna module isopposed to the printed circuit board and arranged in parallel with theprinted circuit board, the planar antenna module having anelectromagnetic radiation surface substantially flush with a surface ofthe information-processing apparatus during operation of the wirelesscommunication device, the electromagnetic radiation surface beingelectrically connected to the printed circuit board.
 15. Aninformation-processing apparatus for performing wireless communication,comprising: a housing; a display unit rotatable, with respect to thehousing, between an opened position and a closed position, and having afront surface and a back surface, the back surface having a recesstherein; and a wireless communication device removably provided in therecess and comprising: a printed circuit board having electroniccomponents thereon configured to perform wireless communication; a coverwhich covers the printed circuit board and the electronic components;and a planar antenna module provided in an upper surface of the coversuch that the planar antenna module is opposed to the printed circuitboard and arranged in parallel with the printed circuit board, theplanar antenna module having an electromagnetic radiation surfacesubstantially flush with the back surface of the display unit duringoperation of the wireless communication device, the electromagneticradiation surface being electrically connected to the printed circuitboard.
 16. An information-processing apparatus according to claim 15,wherein the display unit incorporates a flat panel display exposed atthe front surface and having a back surface covered with a metal platefor shielding against electromagnetic waves.
 17. Aninformation-processing apparatus for performing wireless communication,comprising: a housing; a display unit rotatably connected to thehousing, the display unit having a surface with a recess providedtherein; a first printed circuit board provided in the display unit, thefirst printed circuit board having a first connector; and a wirelesscommunication device removably provided in the recess, the wirelesscommunication device comprising: a second printed circuit board havingelectronic components and a second connector thereon, the secondconnector for connecting to the first connector when the wirelesscommunication device is stored in the recess; and an electromagneticradiation surface configured to form a part of the surface of thedisplay unit when the wireless communication device is stored in therecess.
 18. The information-processing apparatus according to claim 17,wherein the wireless communication device includes an antenna having theelectromagnetic radiation surface.